Liquid refrigerant cooled motor feed assurance means



R. E. RAYNER 3,331,216

LIQUID REFRIGERANT COOLED MOTOR FEED ASSURANCE MEANS 7 July 18, 1967Filed Oct. 13, 1965 RAYMOND E. RAYNER FIG. 5

United States Patent 3,331,216 LIQUID REFRIGERANT COOLED MOTOR FEEDASSURANCE MEANS Raymond E. Rayner, Colonia, N.J., assignor to WorthmgtonCorporation, Harrison, N..l., a corporation of Delaware Filed Oct. 13,1965, Ser. No. 495,438 9 Claims. (Cl. 62-218) ABSTRACT OF THE DISCLOSUREThis application discloses the use of a compartmentalized hotwell for acompression refrigeration system which utilizes a refrigerant cooledcompressor drive motor. Dams are shown in the hotwell to provide solidparticle separation and assurance of early and continuous refrigerantflow to the motor.

This invention relates to a refrigeration system. More particularly, theinvention relates to a condenser hotwell for a refrigeration system.Still more particularly, the invention relates to a condenser hotwellfor a refrigeration system which is used as a liquid refrigerant cooledmotor feed assurance means.

Heretofore refrigeration systems using refrigerant to cool thecompressor motors thereof encountered many obstacles, such as cloggingof the feed lines, excessive pressure drops from the point at which thefeed was taken, and permitting harmful foreign matter to enter the motorthereby causing damage or excessive wear to the component thereof.

Accordingly it is an object of the present invention to provide a novelliquid refrigerant cooled motor feed assurance means which overcomes theprior art disadvantages; which is simple, reliable and economical; whichrequires less refrigerant to be stored in the condenser hotwell whileinsuring that the motor will be selectively fed with liquid refrigerantprior to its passage in the systern; which uses dams, partitions,perforated plates or raised inlets to permit maximum straining orsettling of any foreign matter in the liquid refrigerant, whileproviding sufiicient face area therein to keep any pressure drop to aminimum and prevent clogging; which utilizes sufficient floor area so asto reduce and limit any turbulence in the liquid refrigerant which wouldotherwise adversely affect the operation of the expansion device; whichassures a feed of liquid refrigerant for the motor at all times duringnormal operation of the refrigeration system.

Other objects and advantages will be apparent from the followingdescription of one embodiment of the invention and the novel featureswill be particularly pointed out hereinafter in the claims; referencebeing had to the acc-ornpanying drawings forming a part of thisspecification wherein like reference characters designate correspondingparts in the several views. Furthermore, the phraseology or terminologyemployed herein is for purpose of description and not of limitation.

In the drawings:

FIGURE 1 is a diagrammatic illustration of a refrigeration systemembodying the invention.

FIGURE 2 is a perspective, partially cut-away, of the condenser hotwellembodying the invention.

FIGURE 3 is a plan View, partly broken away, of the condenser hotwellembodying the invention.

FIGURE 4 is a sectional view taken along line 44 of FIGURE 3.

FIGURE 5 is a sectional view taken along line 5-5 of FIGURE 4.

In the embodiment of the invention illustrated in the drawings, thenovel liquid refrigerant cooled motor feed ice assurance means isincorporated in a refrigeration system, designated generally as 10.

Refrigeration system 10 is illustrated diagrammatically in FIGURE 1 andincludes, a compressor 12 having a suction inlet 14 connected by conduit16 to the discharge 18 of an evaporator 20, for receiving andcompressing vaporous refrigerant and forwarding the same through outlet22 which connects to conduit 24 to pass the refrigerant to inlet 26 ofcondenser 28. In condenser 28 the refrigerant vapors are condensed inthe usual manner and passed to hotwell 30 from which a portion of theliquid refrigerant will be delivered in line 32 to cool motor 34 used topower compressor 12. Motor 34 will exhaust the refrigerant in line 36int-o evaporator 20. The last of the liquid refrigerant in hotwell 30will pass through an expansion device which meters the liquidrefrigerant therefrom, from which it will enter line 38 and pass intothe inlet 40 of evaporator 20. In evaporator 20 the refrigerant will beevaporated and returned to the gaseous state from which it will beWithdrawn through line 16 for delivery to compressor 12 whereby thecycle will be continuously repeated.

Hotwell 30 includes a collection chamber 42 designed to receive a supplyof saturated or slightly subcooled liquid refrigerant normally atcondenser pressure directly from the condenser 28 through holes 44 inshell plate 46 of condenser 28, which holes are positioned directlyabove the collection chamber 42. This is made possible by having casing48 of hotwell 30 connected directly to shell plate 46 in such a manneras to position holes 44 in super position to collection chamber 42.Adjacent collection chamber 42 is a feed chamber 50 which includes amotor feed chamber 52 and an evaporator feed chamber 54.

Darn 56 separates collection chamber 42 and feed chamber 50 so that thecollection chamber is substantially smaller than the feed chamber, beingapproximately to /3 the area thereof. A partition 58 extends the lengthof feed chamber 50 to separate motor feed chamber 52 and evaporator feedchamber 54 so that the area of motor feed chamber 52 is between A to /3the size of evaporator feed chamber 54.

The inlet 60 of line 32 extends a short distance above the bottom 62 ofcasing 48. Likewise the side walls 64 of sump 66 extend a short distanceabove bottom 62.

The expansion device 68 as shown operates responsive to the level ofliquid refrigerant collected in evaporator feed chamber 54 and serves tomaintain a seal between the high pressure and low pressure side ofrefrigeration system 10. The particular expansion device shown is afloat controlled valve 70 which meters the passage of liquid refrigerantfrom evaporator feed chamber 54 and sump 66 into line 33 for passage toevaporator 20. Valve 70 has a seat 72 which will normally prevent thepassage of refrigerant into line 38. A stem 74 extends from seat 72 andhas the end thereof remote from seat 72 in slidable engagement with rod76 whereby on movement of rod 76 the stem 74 and the connected seat 72will be raised and lowered responsive to the liquid level of therefrigerant in chamber 54. This is accomplished by having one end of rod76 connected to a float 78, while the other end thereof is pivotablyconnected against one of the walls 64 of sump 66, as at 80. By suitablypositioning float 78 seat 72 may be opened or closed responsive topredetermined levels of the liquid refrigerant in chamber 54. If desiredthe opening of seat 72 may be substantially delayed to provide for asufiicient supply of liquid refrigerant to be continuously delivered tomotor 34 from feed chamber 52.

However in the present embodiment darn 56 is formed with a differentheight on either side of partition 58 so that the top 82 adjacentchamber 54 is substantially at 3 the same level as top 84 of partition58. The top 86 of dam 56 adjacent chamber 52 is substantially lower forpurposes more fully described hereinafter.

A cover plate 88 extends from top 86 of dam 56 the full length and widthof motor feed chamber 52. Cover plate 88 is formed with a plurality ofperforations as at 90, the individual cross-sectional area of which issubstantially smaller than the cross sectional area of inlet 60 of line32.

The liquid refrigerant from condenser 28 will pass through holes 44 asit condenses to be collected in collection chamber 42 at substantiallycondenser pressure and a saturated or slightly subcooled temperature. Asthe amount of the liquid refrigerant in chamber 42 increases it willshortly reach the height of top 86 and cover plate 88 so that it willbegin to pass over cover plate 88. Perforations 90 in cover plate 88will permit the liquid refrigerant to enter motor feed chamber 52.

Collection chamber 42 will permit initial settling of foreign matter inthe liquid refrigerant. Any foreign matter not settled therein, iflarger than the cross-sectional area of perforations 90 will be caughton cover plate 88. Additionally, a secondary settling action is affordedby raising the inlet 60 above the bottom 62 of casing 48. These combinedfeatures act to settle and strain out any foreign matter in the liquidrefrigerant. The utilization of the cover plate 88 whose face area ismany times that of the cross-sectional area of inlet 60 will permit thepassage of the liquid refrigerant at a minimum pressure drop whilepreventing both clogging and passage of harmful foreign matter whichmight damage the motor 34.

As the height of liquid refrigerant in collection chamber 42 reaches top82, the liquid refrigerant will also begin to enter evaporator feedchamber 54 where secondary straining and settling will be accomplishedby the raised sides 64 of sump 66, prior to permitting the passage ofliquid refrigerant from chamber 54 and sump 66 in line 38 to evaporator20. Thereafter liquid refrigerant will be delivered to collectionchamber 42 from condenser 28, the amount delivered being dependent uponthe operating conditions of the system. However, regardless of thecapacity at which system operates collection chamber 42 willcontinuously permit the liquid refrigerant to be delivered to motorchamber 52 whether or not liquid refrigerant is being delivered toevaporator feed chamber 54. In this way adequate cooling of motor 34 isinsured by providing a full feed of liquid refrigerant at all timesduring normal operation, regardless of the loads on refrigeration system10.

Additionally the total quantity of refrigerant in system 10 need not beexcessive, while still permitting suflicient area in evaporator feedchamber so as to reduce turbulence and its detrimental effects on float78 and valve 70.

It will be understood that various changes in the details, materials,arrangement of parts and operating conditions which have beenhereindescribed and illustrated in order to explain the nature of theinvention may be made by those skilled in the art within the principlesand scope of the invention as expressed in the claims.

What is claimed is:

1. A hot well for a refrigeration system having a compressor, acondenser, and an evaporator connected by conduit means into a closedrefrigeration loop, the compressor driven by a motor, the hotwellcomprising:

(a) a casing having a chamber formed therein in communication with thecondenser to receive liquid refrigerant therefrom;

(b) dam means dividing the chamber into a collecting chamber, a motorfeed chamber and an evaporator feed chamber;

(c) conduit means connected between the motor and the motor feedchamber;

(d) means including a float valve disposed in the evaporator feedchamber to meter the liquid refrigerant passing into the evaporator; and

(e) the section of the dam means bordering the motor feed chamber havinga height which is less than the height of the section bordering theevaporator feed chamber whereby straining of the refrigerant in the 5collecting chamber and early continuous refrigerant flow to the motorwill be assured.

2. The combination claimed in claim 1 wherein:

(a) the evaporator feed chamber of larger area than either thecollection chamber is or the motor feed chamber to permit maximumstraining of the liquid refrigerant and to provide minimum turbulence ofthe liquid refrigerant therein.

3. The combination claimed in claim 2 wherein:

(a) the motor feed chamber is of smaller area than the collectionchamber whereby a continuous feed of liquid refrigerant thereto isreadily maintained.

4. The combination claimed in claim 1 wherein:

(a) the float valve having a raised inlet to serve as a secondarystrainer to limit the passage of foreign matter in the liquidrefrigerant thereto, and

(b) the motor feed conduit means having a raised inlet to serve as asecondary strainer to limit the passage of foreign matter in the liquidrefrigerant thereto.

5. A hotwell for a refrigeration system having a compressor, acondenser, and an evaporator connected by conduit means into a closedrefrigeration loop, the compressor driven by a motor, the hotwellcomprising:

(a) a casing having a chamber formed therein in communication with thecondenser to receive liquid refrigerant therefrom;

(b) dam means dividing the chamber into a collecting chamber, a motorfeed chamber and an evaporator feed chamber;

(c) conduit means connected between the motor and the motor feedchamber;

(d) a perforated cove-r plate extending over the motor feed chamber toprevent the passage of foreign matter in the liquid refrigerant into themotor feed chamher, the Perforated cover plate having a face area manytimes larger than the motor feed conduit means to prevent cloggingthereof and to limit the pressure drop therethrough to a minimum;

(e) means including a float valve disposed in the evaporator feedchamber to meter the liquid refrigerant passing therefrom into theevaporator; and

(f) the section of the dam means bordering the motor feed chamber havinga height which is less than the height of the section bordering theevaporator feed chamber whereby straining of the refrigerant and earlycontinuous refrigerant flow to the motor will be assured.

6. A hotwell for a refrigeration system having a motor drivencompressor; a condenser, and an evaporator connected by conduit meansinto a closed refrigeration loop, the hotwell comprising:

(a) a reservoir container adapted to receive liquid refrigerant from thecondenser;

(b) a motor feed container having an outlet connected to a conduit forsupplying refrigerant to the motor;

(c) means for allowing flow from the reservoir into the motor feedcontainer when the height of the refrigerant in the reservoir exceeds apredetermined value;

((1) an evaporator feed container having an outlet connected to aconduit for supplying refrigerant to the evaporator and a floatcontrolled valve for controlling the flow into the conduit so as tomaintain a liquid seal between the evaporator and the condenser; and

(e) means for allowing flow from either the reservoir or the motor feedcontainer into the evaporator feed container when the level ofrefrigerant within the motor feed container reaches a predeterminedvalue.

7. The hotwell defined in claim 6 wherein the means 75 for allowing flowinto the motor feed container include walls which form dams for allowingfiow into the containers when the refrigerant level behind the damreaches a prescribed value.

8. The hotwell defined in claim 7 including a perforated cover plateover the motor feed container.

9. A hotwell for a refrigeration system having a compressor, acondenser, and an evaporator connected by conduit means into a closedrefrigeration loop, the compressor driven by a motor, the hotwellcomprising:

(a) a casing below the condenser having a chamber therein receivingrefrigerant from the condenser;

(b) wall means in the chamber forming,

(1) a reservoir chamber,

(2) a motor feed container having an outlet communicating with the motorfor supplying refrigerant thereto, and

(3) an evaporator feed container having an outlet communicating with theevaporator for supplying refrigerant thereto;

(c) the Wall means having an opening at a first level for allowingrefrigerant to flow from the reservoir into the motor feed container andsecond opening at a higher level than the first for allowing refrigerantto flow from the reservoir into the evaporator feed container.

References Cited UNITED STATES PATENTS 2,921,445 1/1960 Ashley 62-5 053,022,638 2/1962 Caswell 62-505 X 3,122,894 3/1964 Bernhard 62505 X3,218,825 11/1965 McClure 62-505 MEYER PERLIN, Primary Examiner.

1. A HOT WELL FOR A REFRIGERATION SYSTEM HAVING A COMPRESSOR, ACONDENSER, AND AN EVAPORATOR CONNECTED BY CONDUIT MEANS INTO A CLOSEDREFRIGERATION LOOP, THE COMPRESSOR DRIVEN BY A MOTOR, THE HOTWELLCOMPRISING: (A) A CASING HAVING A CHAMBER FORMED THEREIN INCOMMUNICATION WITH THE CONDENSER TO RECEIVE LIQUID REFRIGERANTTHEREFROM; (B) DAM MEANS DIVIDING THE CHAMBER INTO A COLLECTING CHAMBER,A MOTOR FEED CHAMBER AND AN EVAPORATOR FEED CHAMBER; (C) CONDUIT MEANSCONNECTED BETWEEN THE MOTOR AND THE MOTOR FEED CHAMBER; (D) MEANSINCLUDING A FLOAT VALVE DISPOSED IN THE EVAPORATOR FEED CHAMBER TO METERTHE LIQUID REFRIGERANT PASSING INTO THE EVAPORATOR; AND (E) THE SECTIONOF THE DAM MEANS BORDERING THE MOTOR FEED CHAMBER HAVING A HEIGHT WHICHIS LESS THAN THE HEIGHT OF THE SECTION BORDERING THE EVAPORATOR FEEDCHAMBER WHEREBY STRAINING OF THE REFRIGERANT IN THE COLLECTING CHAMBERAND EARLY CONTINUOUS REFRIGERANT FLOW TO THE MOTOR WILL BE ASSURED.